No cookies, and so no banner. Mixpanel's own opt-out works by setting a flag in the visitor's browser cookie or local storage, which is a fair description of how it recognises people generally. Skomi derives identity on the server from a secret replaced every day, so on the default setting there is nothing on the device and nothing to consent to.
It works without an event model. Mixpanel is only as good as the events you defined, and defining them well is a project with a meeting in it. Skomi's traffic, sources, goals and funnels come from one script.
Sites are first-class, not a special case. Mixpanel grew up measuring product usage; page views, referrers and campaigns are things it can do rather than the shape it was built around.